Lubricated plug valve



LUBRICATED PLUG VALVE Filed Dec. 29, 1945 3 2 Sheets-heet 1TQPUNGE'SMITH INVENTOR.

Sept. 25, 1951 s rr 2,568,935

LUBRICATED PLUG VALVE Filed Dec. 29, 1945 2 Sheets-Sheet 2 JOPLBNG P5MHTH INVENTOR.

BY my 4 6% vi Patented Sept. 25,l951

(lFFlCE- LUBRICATED PL'IjG vALvir J opling P. Smith, Houston, Tex,assignor to Garrott Brass & Machine Company, Inc.

Application December 29, 1945, Serial No. 638,096

1 Claim. 1

The invention relates to what is generally known as a kelley cock orplug valve. Valves of this type are generally used in a string of pipeemployed in the rotary method of drilling wells and positioned above thegrief stem or kelley connected to the top of the string of pipe. Thevalve is usually utilized to close the flow through the pipe undervarious circumstances and conditions.

While the invention will be described as applied to this particular use,it is to be understood that the valve may be utilized as a plug valve inother situations.

It is one of the objects of the invention to provide a lubricated pluvalve wherein a seal may be maintained around the downstream flow port.

Another object of the invention is to provide a removable seat platecarrying a sealin material reservoir for plug valves.

Still another object of the invention is to provide a kelley cockwherein the high pressure is used to automatically maintain sealingmaterial about the downstream port when the valve is closed.

Other and further objects of the invention will be readily apparent whenthe following description is considered in connection with theaccompanying drawings, wherein Fig. l is a vertical sectional viewillustrating the kelley cock and the various parts thereof in closedposition;

Figs. 2 and 3 are sections taken on the lines 2--2 and 33 respectivelyof Fig. 1.

In Fig. l the housing 2 is provided with a threaded pin 3 for connectionto the pipe while the upper end is provided with a threaded box 4 toalso receive the swivel. The housing has a flow passage 5 therethroughwhich is interrupted or intersected by the plug chamber 6. This formsthe flow ports I and 8 and it is intended that 8 will be the upstream orhigh pressure flow port while I is the downstream or low pressure flowport.

Arranged for rotation in the chamber 6 is the plug I0 having the stem ll thereon which has its outer end l2 flush with the curved surface I3which forms the surface of the housing. A noncircular portion l4 permitsintroduction of a tool to turn the plug.

The plug is retained in place by the thrust plates It held in positionby a cap I! which is sealed to the housing with the seal rings IB withthe entire assembly held in place by the cap screws l9. In order to sealabout the stem a packing 20 is normally urged to sealing position by acoil spring 2|.

The plug I0 is of peculiar formation as best seen in Figs. 1 and 2 andhas the flow passage therethrough. One side of the plug is recessed at26 over about half of its periphery so as to receive a semi-cylindricalseat plate 21 which fits into the recess and whose outer face 28 thencompletes the periphery 29 of the plug. The base of the plug is providedwith a lug or projection 30 slidable in a recess 31 so as to limit theturning movement of the plug to approximately one quarter of a turn. Thespindle 32 fitting in the recess 33 in the base of the plug centers theplug and permits rotation thereof.

The seat plate is intended to form a seal with the surface of thechamber 6 in the downstream flow port 1. Small springs 35 tend to urgethe seat plate away from the plug and against the flow port 1. In orderto maintain a seal about the fiow port I, the seat plate has adistribution groove 37 in the face 28 thereof. This groove preferably iscircular and as seen in Fig. 1 extends about the fiow port I when thevalve is in closed position.

In order to feed sealing material into this groove an injection fitting39 is disposed in the opening 40 in the body of the valve and thisopening is arranged to be closed with the screw 4|. A check valve 42prevents leakage of the material from inside of the valve.

The material being injected through the fitting passes into the conduit43 which is arranged to connect the reservoir 46 with the distributiongroove 31 when the valve is in closed position.

In order that a supply of sealing material may be disposed in the valveand available for sealing the plug when the valve is manipulated, theplug [0 has a transverse opening 45 therein which is arranged to receivea hollow cylindrical reservoir 46. This reservoir is shown threaded at41 into an opening in the plate 21 so that it is supported by the platein the opening 45. The end of the reservoir 46 which is adjacent theface of the plate has a passage 48 therein by which sealing material maypass into the reservoir when it is introduced through the fitting 39.

A barrier 50 is slidable in the hollow reservoir and will be moveddownwardly as seen in Fig. 1 when the sealing material is introduced.Another opening 52 in the base of the reservoir is arranged to admitpressure from the upstream side of the plug valve, that is, the higherpressure which is against the valve. This pressure moving into thereservoir will tend to raise the barrier 50 when the valve is in use soas to maintain a seal of material in the groove 31.

An advantage oi the assembly just described is that the valve may beused for long periods of time without servicing to introduce sealingmaterial and further when the parts of the valve are to be renewed orrepaired, the plate 21 and the reservoir 26 can be removed as a unit anda new unit comprising the plate and reservoir applied to the plug l0.

It is believed that the operation and use of the valve will be readilyapparent from the foregoing description.

What is claimed is:

A drill stem kelley valve including a housing, a transverse plug chambertherein, a flow passage through the housing and crossing said chamber toprovide a downstream seat at the. topof said chamber, a rotatable plugin said chamber, an arcuate seat plate recessed into said plug andmovable therewith, a face on said plate extending across said seat whenthe plug is in closingposition, and means to provide a seal on the faceof said plate is sz x q p istr bu iqn m r n t we en i n aid 'dewestr m sat, a. r er i member-wane bx he late. em miaqtie die? RE I TERENC EIQCITED The following references are of record in the file of this patent:

ITED STATES PATENTS Number Name Date 2,176;7;-3.0. Church Oct. 17, 19392,269,887 Sharp Jan. 13, 1942 aaaieia SEEK: 18, 1945 2,418,404 GreenleeApr. 1, 1947 FOREIGN PATENTS Member C u tr D te,

